PMG Unable to Deliver Mail

[info.it]

After PMG upgraded to 8.2, we frequently receive the following errors when receiving external emails. How can I resolve this?

2025-08-05T13:20:52.798370+08:00 pmg01 postfix/smtpd[3451354]: connect from mg1.xxx.com[185.252.36.100]
2025-08-05T13:20:53.780002+08:00 pmg01 postfix/smtpd[3451354]: Anonymous TLS connection established from mg1.xxx.com[185.252.36.100]: TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
2025-08-05T13:20:55.043889+08:00 pmg01 postfix/smtpd[3451354]: 0A91A800ACD: client=mg1.xxx.com[185.252.36.100]
2025-08-05T13:20:56.812663+08:00 pmg01 postfix/cleanup[3451934]: 0A91A800ACD: message-id=<AS8PR05MB8757D59DEB7462B04B300E5A9822A@AS8PR05MB8757.eurprd05.prod.outlook.com>
2025-08-05T13:20:58.775016+08:00 pmg01 postfix/qmgr[3400383]: 0A91A800ACD: from=<XXX>, size=1255652, nrcpt=5 (queue active)
2025-08-05T13:21:05.144797+08:00 pmg01 postfix/lmtp[3451278]: 0A91A800ACD: to=<xxx>, relay=127.0.0.1[127.0.0.1]:10024, delay=11, delays=4.5/0/0.04/6.3, dsn=4.4.0, status=deferred (host 127.0.0.1[127.0.0.1] said: 451 4.4.0 detected undelivered mail to <xxx> (in reply to end of DATA command))

 

[Stoiko Ivanov]

could you please share the complete logs of the mail - usually there should be logs from pmg-smtp-filter present as well.

without further information I would guess that something caused the mailprocessing to take too long and thus it was not done within the time out...